TABLE 3.
Performance of PCE EIA tested on self-taken vulvovaginal-swab specimens
| Final result | No. of results for PCE EIA
|
|||
|---|---|---|---|---|
| Positive | Negative | NGZa | Total | |
| Bristol laboratoryb | ||||
| True positive | 52 | 19 | 3 | 74 |
| True negative | 17 | 1,379 | 7 | 1,403 |
| Total | 69 | 1,398 | 10 | 1,477 |
| Birmingham laboratoryc | ||||
| True positive | 39 | 30 | 3 | 72 |
| True negative | 7 | 1,188 | 5 | 1,200 |
| Total | 46 | 1,218 | 8 | 1,272 |
NGZ, negative gray zone.
Results including the negative-gray-zone results with nucleic acid amplification test confirmation were as follows: sensitivity, 74.3% (95% CI, 62.8 to 83.8%); specificity, 98.8% (95% CI, 98.1 to 99.3%); positive predictive value, 72.2% (95% CI, 60.4 to 82.1%); and negative predictive value, 98.1% (95% CI, 97.3 to 98.8%). Results with the negative-gray-zone results treated as negative were as follows: sensitivity, 70.2% (95% CI, 58.5 to 80.3%); specificity, 98.8% (95% CI, 98.1 to 99.3%); positive predictive value, 75.4% (95% CI, 63.5 to 84.9%); and negative predictive value, 98.4% (95% CI, 97.6 to 99%).
Results including the negative-gray-zone results with nucleic acid amplification test confirmation were as follows: sensitivity, 58.3% (95% CI, 46.1 to 69.8%); specificity, 99.4% (95% CI, 98.8 to 100%); positive predictive value, 85.7% (95% CI, 72.8 to 94.1%); and negative predictive value, 97.5% (95% CI, 96.5 to 98.3%). Results with the negative-gray-zone results treated as negative were as follows: sensitivity, 54.2% (95% CI, 42.0 to 66.0); specificity, 99.0 (95% CI, 98.3 to 99.5); positive predictive value, 84.8% (95% CI, 71.1 to 93.7%); and negative predictive value, 97.3% (95% CI, 96.2 to 98.1%).